Grid Footer

I’m attempting to create a footer for my grid but it I can’t make it work properly.

I’m using the following method as I don’t know of any other way.

mygrid.attachFooter(“A,B,C”,[“text-align:left;”,“text-align:right;”,“text-align:right”]);

As soon as I add this line of code the grid doesn’t load anymore.

Am I doing something wrong or does attachFooter require a specific js file?

Also, provided that I can make the footer appear, how do I sum the column values in the footer cell?

Never mind, after a lot of searching I found that this is Pro only.
It should state that whenever the function is mentioned in the documentation.